. (1) The American ideal of a lush green lawn is borrowed from England, where the cool, misty climate makes it easy to grow grass. (2) In America, however, lawns are an energy-intensive, wasteful, and nonproductive form of landscaping. (3) To begin with, achieving a picture-perfect lawn requires gallons of expensive fertilizer and hazardous pesticides that pollute groundwater and run off into lakes and rivers. (4) In addition, lawn owners often exterminate the insects, moles, and gophers that play a part in the balance of nature. (5) Equally destructive is the constant watering lawns require, often where water is a limited resource. (6) Finally, the lawn must be mowed on a regular basis to give it that green carpet effect, requiring endless output of human and mechanical energy. (7) After all the labor and expense, the final result is a flat carpet that lacks interesting features, wildlife, or edible produce.

Consider a slotted aloha system, where the time slot equals the fixed duration of each packet. assume that there are 4 stations a,b,c,d sharing the medium. (a) stations a,b,c,d receive one packet each from higher layers at times 1.3, 1.5, 2.6,5.7 respectively. show which transmissions take place when, according to the slottedaloha protocol; describe all transmissions until all four packets have been successful.when needed, each station has access to the following sequence of random number, provided by a random number generator and drawn uniformly between 0 and 1: (1) station a draws numbers: 0.31, 0.27, 0.78, 0.9, 0.9, 0.11, 0. (2) station b draws numbers: 0.45, 0.28, 0.11, 0.83, 0.37, 0.22, 0. (3)station c draws numbers: 0.1, 0.2, 0.3, 0.4, 0. (4) station d draws numbers: 0.36, 0.77, 0.9, 0.1, 0.1, 0.1, 0.1, 0. (b) in slotted aloha, a station transmits in each time slot with a given probability. what probabilities would you assign to each of the four stations so as to: (i) maximize the efficiency of the protocol? (ii) maximize fairness among the four stations? (c) will the efficiency increase or decrease if we modify slotted aloha as follows: (i) get rid of slots and allow stations to transmit immediately? (ii) implement carrier sensing? (iii) implement collision detection? (iv) implement collision avoidance?

How might the success of your campaign be affected if you haven’t carefully completed all field data or if you accidentally insert the wrong merge field in the document?

Develop a function to create a document in the mongodb database “city” in the collection “inspections.” be sure it can handle error conditions gracefully. a. input -> argument to function will be set of key/value pairs in the data type acceptable to the mongodb driver insert api call b. return -> true if successful insert else false (require a screenshot)